Alopecia universalis is an advanced form of alopecia areata, characterized by complete loss of hair on all hair-bearing areas. It is currently believed to be an autoimmune disorder. The development of alopecia during treatment with tumor necrosis factor alpha (TNF-α) inhibitors is a rarely observed adverse event. This case describes a 56-year-old female patient with rheumatoid arthritis (RA), who developed alopecia universalis during treatment with adalimumab. There was no improvement in alopecia despite withdrawal of adalimumab. It is believed that interferon-α is the main cytokine involved in promoting inflammation in hair loss after blocking TNF-α by TNF inhibitors. Risk/benefit ratio of maintenance and discontinuation of the drug should be weighed up when alopecia appears during treatment with TNF inhibitors.